@mixin transform($value) {
  -webkit-transform: $value; /* Safari */
  -moz-transform: $value;
  -ms-transform: $value; /* IE 9 */
  -o-transform: $value;
  transform: $value; /* 标准语法 */
}

@mixin animation($value) {
  -webkit-animation: $value;
  -moz-animation: $value;
  -ms-animation: $value;
  -o-animation: $value;
  animation: $value;
}

@mixin transition($value) {
  -webkit-transition: $value;
  -moz-transition: $value;
  -ms-transition: $value;
  -o-transition: $value;
  transition: $value;
}

.full-screen {
  width: 100%;
  height: 100%;
  position: absolute;
  left: 0;
  top: 0;
}